Button battery

Abstract

Provided in the present application is a button battery. The button battery comprises a casing and a laminated cell, wherein the casing comprises a bottom casing, a terminal post and a top cover. The top cover is hermetically connected to the bottom casing. The terminal post is connected to the top cover. The bottom casing and the terminal post lead out different polarities. The laminated cell is arranged in the casing. In the stacking direction of the laminated cell, the laminated cell comprises a first single-sided electrode sheet and a second single-sided electrode sheet, which are located on the outermost sides. The first single-sided electrode sheet and the second single-sided electrode sheet have opposite polarities. The first single-sided electrode sheet comprises a first current collector and a first active material layer. In the stacking direction of the laminated cell, the surface of the first current collector facing the terminal post is directly electrically connected to the terminal post. The first active material layer is arranged on the surface of the first current collector facing away from the electrode post. The second single-sided electrode sheet comprises a second current collector and a second active material layer. The surface of the second current collector facing away from the terminal post is directly electrically connected to the bottom casing. The second active material layer is arranged on the surface of the second current collector facing the terminal post.

Description

button battery

[0001] Cross-reference of related applications

[0002] This application claims priority to Chinese patent application 202510056264.7 entitled “Button Battery”, filed on January 14, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of batteries, and in particular to a button cell battery. Background Technology

[0004] Button batteries are widely used in electronic devices such as computers, clocks, and calculators. Improving the energy density of button batteries is one of the research directions in battery technology development. Summary of the Invention

[0005] In view of the above problems, this application provides a button cell battery that can help improve the energy density of the button cell battery.

[0006] This application provides a button cell, comprising a casing and stacked cells. The casing includes a bottom casing, terminals, and a top cover. The top cover is sealed to the bottom casing. The terminals are connected to the top cover. The bottom casing and terminals have different polarities. The stacked cells are disposed within the casing. Along the stacking direction of the stacked cells, the stacked cells include a first single-sided electrode and a second single-sided electrode located on the outermost side. The first single-sided electrode and the second single-sided electrode have opposite polarities. The first single-sided electrode includes a first current collector and a first active material layer. Along the stacking direction of the stacked cells, the surface of the first current collector facing the terminals is directly electrically connected to the terminals. The first active material layer is disposed on the surface of the first current collector facing away from the terminals. The second single-sided electrode includes a second current collector and a second active material layer. The surface of the second current collector facing away from the terminals is directly electrically connected to the bottom casing. The second active material layer is disposed on the surface of the second current collector facing the terminals.

[0007] The button cell of this application embodiment includes a casing and stacked cells disposed within the casing. The outermost first and second single-sided electrodes of the stacked cells are directly electrically connected to the terminal post and the bottom shell, respectively, eliminating the need for an additional adapter plate between the stacked cells and the casing. In the stacking direction of the stacked cells, no space needs to be reserved between the stacked cells and the casing to avoid the adapter plate, thereby improving the structural compactness of the button cell in the stacking direction. This structural design helps to reduce the overall size of the button cell in the stacking direction, thus reducing the overall volume of the button cell and improving its energy density.

[0008] In one or more of the above optional embodiments, the button cell includes a first adhesive member that bonds a first current collector to an electrode post.

[0009] The first adhesive component can fix the position of the laminated cell inside the housing, reducing the possibility that the laminated cell may shake inside the housing, causing the terminal and the first current collector to lose their electrical connection.

[0010] In one or more of the above optional embodiments, the electrode post includes a first wall surface and a first protrusion. The first wall surface is disposed facing the stacked battery cell, and the first protrusion protrudes from the first wall surface and abuts against the surface of the first current collector facing the electrode post. Along the stacking direction of the stacked battery cell, there is a first gap between the first wall surface and the first current collector.

[0011] By directly contacting the first protrusion with the first current collector, on the one hand, it helps to reduce the difficulty of making an electrical connection between the terminal and the first current collector, and on the other hand, it helps to ensure that the terminal and the first current collector maintain a stable electrical connection in the assembled button battery, reducing the possibility of poor contact problems such as intermittent connection between the terminal and the first current collector.

[0012] In one or more of the above optional embodiments, the value of the first spacing is greater than 0 micrometers and less than or equal to 50 micrometers.

[0013] In one or more of the above optional embodiments, the first adhesive member is disposed between the pole post and the first current collector, the first adhesive member has a first clearance channel, and the first protrusion passes through the first clearance channel and abuts against the first current collector.

[0014] The first clearance channel is used to avoid the first protrusion, reducing the possibility that the first adhesive component, located between the first protrusion and the first current collector, might affect the electrical connection between the first protrusion and the first current collector. Electrolyte can be filled into the casing of the button battery. The first protrusion can be surrounded by the first adhesive component, preventing electrolyte from wetting the connection area between the first protrusion and the first current collector, reducing the possibility of corrosion in the connection area and thus instability in the electrical connection between the first protrusion and the first current collector.

[0015] In one or more of the above optional embodiments, the electrode post includes a first wall surface and a first recess. The first wall surface is disposed facing the stacked battery cell, the first recess is disposed on the first wall surface, the first recess includes an opening located on the first wall surface, a first adhesive member is disposed in the first recess, the first wall surface abuts against the surface of the first current collector facing the electrode post, and the first adhesive member bonds the first current collector to the electrode post.

[0016] The first wall surface of the terminal post is in direct contact with the surface of the first current collector facing the terminal post. The distance between the first wall surface and the first current collector is zero. This structural design helps to reduce the overall size of the coin cell in the stacking direction of the stacked cells, thereby reducing the overall volume of the coin cell and thus improving its energy density.

[0017] In one or more of the above optional embodiments, the first adhesive is a conductive adhesive and / or a pressure-sensitive adhesive.

[0018] The first adhesive can be a conductive adhesive. The first adhesive itself is conductive, so the electrode and the first current collector can also be electrically connected through the first adhesive.

[0019] The first adhesive component can be a pressure-sensitive adhesive. The first adhesive component does not require heating, solvent activation, or complex curing processes. Bonding can be achieved simply by applying relatively small pressure to the first adhesive component using the electrode post and the first current collector, thus reducing the difficulty of connection.

[0020] In one or more of the above optional embodiments, the first current collector includes a first tab and a first body portion connected together. The first tab and the first body portion are integrally formed. A first active material layer is disposed on the first body portion, and the surface of the first body portion facing the electrode post is directly electrically connected to the electrode post.

[0021] The method of electrically connecting the stacked cells to the terminals via the first main body allows for a reduction in the spacing between the stacked cells and the terminals along the stacking direction. This reduces the overall size of the coin cell and thus improves its energy density. The relatively large area of ​​the first main body also helps to simplify the connection between the first current collector and the terminals.

[0022] In one or more of the above optional embodiments, the button battery includes a first adhesive member that adhesively bonds the terminal post to the first body portion.

[0023] The first main body has a relatively large area. The first main body is bonded to the pole using a first adhesive, which helps to reduce the difficulty of connecting the first adhesive to the first current collector, and also helps to increase the connection area between the first current collector and the pole, thereby improving the connection stability between the first current collector and the pole.

[0024] In one or more of the above optional embodiments, the first current collector includes a first tab, a first main body, and a first folded portion connected together. The first tab, the first main body, and the first folded portion are integrally formed. A first active material layer is disposed on the first main body, the first folded portion is folded relative to the first main body, the first folded portion is located between the first main body and the electrode post, and the surface of the first folded portion facing the electrode post is directly electrically connected to the electrode post.

[0025] The first current collector is designed with a first folding section, which allows the stacked cell to be connected and fixed to the terminal block first, and then the top cover to be closed. This helps to reduce the difficulty of connecting the stacked cell to the terminal block and improve the connection stability and efficiency between the stacked cell and the terminal block.

[0026] In one or more of the above optional embodiments, the first folded portion is welded to the terminal post; or, the button battery includes a first adhesive member that bonds the first folded portion to the terminal post.

[0027] The first fold and the terminal are connected by welding, which helps to improve the connection strength and stability between the first fold and the terminal, and reduces the possibility that the first fold and the terminal will become disconnected during the use of the button battery.

[0028] By bonding the first folding part to the pole post, the connection difficulty between the first folding part and the pole post can be reduced, and it is also convenient to observe and detect the bonding status between the first folding part and the pole post. In addition, there is no need to consider the problems of over-welding and cold welding caused by welding, nor is there any need to consider the welding marks left by welding.

[0029] In one or more of the above optional embodiments, the area of ​​the first folded portion is greater than or equal to the area of ​​the first main body portion.

[0030] When the stacked battery cell expands, the first main body and the first folded part come into contact. The first folded part can support the first main body as a whole and apply a reaction force to the first main body as a whole. This can help the first main body to be subjected to uniform force, reduce the possibility of stress concentration areas caused by uneven force on the first main body, and prevent the first active material layer from peeling off and falling off the first main body in the stress concentration area.

[0031] In one or more of the above optional embodiments, the surface area of ​​the electrode facing the laminated cell is greater than or equal to the area of ​​the first main body.

[0032] When the laminated cell expands, the electrode post and the first folding part can simultaneously support the entire first main body and apply a reaction force to the entire first main body. This can help to ensure that the entire first main body is subjected to uniform force, reduce the possibility of stress concentration areas caused by uneven force on the first main body, and prevent the first active material layer from peeling off and falling off the first main body in the stress concentration area.

[0033] In one or more of the above alternative embodiments, the bottom shell has a bottom wall, and the button battery includes a second adhesive member that adhesively bonds a second current collector to the bottom wall.

[0034] The second adhesive component can fix the position of the laminated cell inside the housing, reducing the possibility that the laminated cell may shake inside the housing, causing the bottom wall and the second current collector to lose their electrical connection.

[0035] In one or more of the above optional embodiments, the bottom wall has a second wall surface, the bottom shell includes a second protrusion, the second wall surface is disposed facing the stacked cells, the second protrusion is protruding from the second wall surface, the second protrusion abuts against the surface of the second current collector facing the bottom wall, and a second gap is formed between the second wall surface and the second current collector along the stacking direction of the stacked cells.

[0036] By directly contacting the second protrusion with the second current collector, on the one hand, it helps to reduce the difficulty of making an electrical connection between the bottom shell and the second current collector; on the other hand, it helps to ensure a stable electrical connection between the bottom shell and the second current collector in the assembled button battery, reducing the possibility of poor contact problems such as intermittent connection between the bottom shell and the second current collector.

[0037] In one or more of the above optional embodiments, the value of the second spacing is greater than 0 micrometers and less than or equal to 50 micrometers.

[0038] In one or more of the above optional embodiments, the second adhesive is disposed between the bottom wall and the second manifold, the second adhesive has a second clearance channel, and the second protrusion passes through the second clearance channel and abuts against the second manifold.

[0039] The second protrusion can be surrounded by the second adhesive, which prevents the electrolyte from wetting the connection area between the second protrusion and the second current collector, reducing the possibility of corrosion in the connection area between the second protrusion and the second current collector, which could lead to instability in the electrical connection between the second protrusion and the second current collector.

[0040] In one or more of the above optional embodiments, the second current collector includes a second electrode tab and a second main body portion connected together. The second electrode tab and the second main body portion are integrally formed. A second active material layer is disposed on the second main body portion, and the surface of the second main body portion facing away from the electrode post is directly electrically connected to the bottom shell.

[0041] The method of electrically connecting the stacked cells to the bottom shell via the second main body allows for a reduction in the distance between the stacked cells and the bottom shell in the stacking direction. This reduces the overall size of the coin cell in the stacking direction, thereby decreasing its overall volume and improving its energy density. The relatively large area of ​​the second main body also helps to simplify the connection between the second current collector and the bottom shell.

[0042] In one or more of the above optional embodiments, the bottom shell has a bottom wall, and the button battery includes a second adhesive member that adhesively bonds the second body portion to the bottom wall.

[0043] The second main body has a relatively large area. The second main body is bonded to the bottom wall using a second adhesive, which helps to reduce the difficulty of connecting the second adhesive to the second manifold, and also helps to increase the connection area between the second manifold and the bottom wall, thereby improving the connection stability between the second manifold and the bottom wall.

[0044] In one or more of the above optional embodiments, the second current collector includes a connected second tab, a second main body, and a second folded portion. The second tab, the second main body, and the second folded portion are integrally formed. A second active material layer is disposed on the second main body, the second folded portion is folded relative to the second main body, the second folded portion is located between the second main body and the bottom shell, and the surface of the second folded portion facing away from the electrode post is directly electrically connected to the bottom shell.

[0045] The second current collector is equipped with a second folding section, which allows the stacked battery cell to be first connected and fixed to the bottom shell, and then the stacked battery cell to be installed into the bottom shell. This helps to reduce the difficulty of connecting the stacked battery cell and the bottom shell, and improve the connection stability and efficiency between the stacked battery cell and the bottom shell.

[0046] In one or more of the above optional embodiments, the bottom shell has a bottom wall, and the second folded portion is welded to the bottom wall; or, the button battery includes a second adhesive member, which adhesively bonds the second folded portion to the bottom wall.

[0047] The second fold and the bottom wall are connected by welding, which helps to improve the connection strength and stability between the second fold and the bottom wall, and reduces the possibility that the second fold and the bottom wall will become disconnected during the use of the button battery.

[0048] By bonding the second folded part to the bottom wall, the connection between the second folded part and the bottom wall can be reduced, and the bonding status between the second folded part and the bottom wall can be easily observed and detected.

[0049] In one or more of the above optional embodiments, the area of ​​the second folded portion is greater than or equal to the area of ​​the second main body portion.

[0050] When the stacked cell expands, the second main body and the second folded part come into contact. The second folded part can support the second main body as a whole and apply a reaction force to the second main body as a whole. This can help the second main body to be subjected to uniform force, reduce the possibility of stress concentration areas caused by uneven force on the second main body, and prevent the second active material layer from peeling off and falling off the second main body in the stress concentration area.

[0051] In one or more of the above optional embodiments, the laminated cell includes a first double-sided electrode and a second double-sided electrode. The first single-sided electrode and the second single-sided electrode are alternately stacked. The first single-sided electrode and the first double-sided electrode have the same polarity. The first single-sided electrode and each of the first double-sided electrodes are electrically connected. The second single-sided electrode and the second double-sided electrode have the same polarity. The second single-sided electrode and each of the second double-sided electrodes are electrically connected.

[0052] In one or more of the above optional embodiments, the first single-sided electrode includes a first tab, the first double-sided electrode includes a third tab, the first tab and each third tab are gathered together and welded along the stacking direction of the stacked cells to form a first gathered portion, the first gathered portion is a one-piece structure.

[0053] The first gathering section is a one-piece structure. The first and third tabs can be gathered and welded towards the bottom wall or towards the top cover along the stacking direction of the laminated cells. The first gathering section is a one-piece structure, which means that the first and third tabs do not need to be gathered towards the bottom wall and then folded back towards the top cover, or gathered towards the top cover and then folded back towards the bottom wall. This helps to reduce the space occupied by the first and third tabs, which helps to reduce the overall size of the button cell, thereby reducing the overall volume of the button cell and thus helping to improve the energy density of the button cell.

[0054] In one or more of the above optional embodiments, the second single-sided electrode includes a second tab, the second double-sided electrode includes a fourth tab, the second tab and each of the fourth tabs are gathered together and welded along the stacking direction of the stacked battery cell to form a second gathered portion, the second gathered portion is a one-piece structure.

[0055] The second gathering section is a one-piece structure. The second and fourth tabs can be gathered and welded towards the bottom wall or towards the top cover along the stacking direction of the stacked cells. The second gathering section is a one-piece structure, which means that the second and fourth tabs do not need to be gathered towards the bottom wall and then folded back towards the top cover, or gathered towards the top cover and then folded back towards the bottom wall. This helps to reduce the space occupied by the second and fourth tabs, which helps to reduce the overall size of the button cell, thereby reducing the overall volume of the button cell and thus helping to improve the energy density of the button cell.

[0056] In one or more of the above optional embodiments, the first single-sided electrode is a cathode electrode and the second single-sided electrode is an anode electrode.

[0057] In one or more of the above optional embodiments, the top cover and the bottom shell are directly electrically connected, the outer shell includes an insulating element, the insulating element connects the pole and the top cover, and the pole and the top cover are insulated and isolated by the insulating element.

[0058] An insulating component connects the terminal post and the top cover. The terminal post and the top cover are insulated from each other by the insulating component. There is no electrical connection between the terminal post and the top cover. Attached Figure Description

[0059] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0060] Figure 1 is a schematic diagram of the structure of a button battery provided in an embodiment of this application;

[0061] Figure 2 is a schematic diagram of the structure of a button battery provided in an embodiment of this application;

[0062] Figure 3 is a partial cross-sectional view of a button battery provided in an embodiment of this application;

[0063] Figure 4 is a partially exploded structural diagram of a button battery provided in an embodiment of this application;

[0064] Figure 5 is a partial structural schematic diagram of a stacked battery cell provided in an embodiment of this application;

[0065] Figure 6 is a partial structural schematic diagram of a stacked battery cell provided in an embodiment of this application;

[0066] Figure 7 is a partial structural schematic diagram of a stacked battery cell provided in an embodiment of this application;

[0067] Figure 8 is a partial cross-sectional view of a button battery provided in an embodiment of this application;

[0068] Figure 9 is a partial cross-sectional view of a button battery provided in an embodiment of this application;

[0069] Figure 10 is a partially exploded structural diagram of a button battery provided in an embodiment of this application;

[0070] Figure 11 is a partial structural schematic diagram of a stacked battery cell provided in an embodiment of this application;

[0071] Figure 12 is a schematic diagram of the structural changes of a laminated battery cell provided in an embodiment of this application;

[0072] Figure 13 is a schematic diagram of the assembly process of a button battery provided in an embodiment of this application;

[0073] Figure 14 is a partial cross-sectional view of a button battery provided in an embodiment of this application;

[0074] Figure 15 is a partial cross-sectional view of a button battery provided in an embodiment of this application;

[0075] Figure 16 is a partial structural schematic diagram of a stacked battery cell provided in an embodiment of this application;

[0076] Figure 17 is a partial cross-sectional view of a button battery provided in an embodiment of this application;

[0077] Figure 18 is an enlarged view of point M in Figure 17;

[0078] Figure 19 is an enlarged schematic diagram of point W in Figure 17;

[0079] Figure 20 is a partial structural schematic diagram of a button battery provided in an embodiment of this application.

[0080] Explanation of reference numerals in the attached drawings: 10, button battery; 20, outer casing; 201, first protrusion; 202, second protrusion; 21, bottom casing; 21a, second wall surface; 21b, second recess; 211, bottom wall; 22, terminal post; 22a, first wall surface; 22b, first recess; 212, side wall; 221, base; 222, boss; 23, top cover; 231, center through hole; 24, insulating component; 30, laminated cell; 31, first single-sided electrode; 311, first current collector; 3111, first tab; 3112, first main body; 3113, first folded part; 3 12. First active material layer; 32. Second single-sided electrode; 321. Second current collector; 3211. Second tab; 3212. Second main body; 3213. Second folded part; 322. Second active material layer; 33. First double-sided electrode; 331. Third tab; 34. Second double-sided electrode; 341. Fourth tab; 35. Separator; 40. First adhesive; 50. Second adhesive; 60. First gathering part; 70. Second gathering part; 80. Insulating tape; 100. First clearance channel; 110. Second clearance channel; X, stacking direction. Detailed Implementation

[0081] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0082] It should be noted that, unless otherwise stated, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by those skilled in the art to which the embodiments of this application pertain.

[0083] In the description of the embodiments of this application, the technical terms "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0084] Furthermore, technical terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise explicitly defined.

[0085] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0086] In related technologies, a button cell includes a casing and a battery cell. The battery cell is housed within the casing. The battery cell includes multiple first tabs and multiple second tabs. The button cell includes adapter plates. Each of the first and second tabs is welded to a corresponding adapter plate. The first and second tabs are each led out through their respective adapter plates. The additional adapter plates occupy space within the casing, reducing space utilization and resulting in a relatively low energy density for the button cell itself. Energy density refers to the ratio between the discharge energy of a button cell and its volume.

[0087] The button cell battery of this application embodiment can help improve the structural compactness and energy density of the button cell battery.

[0088] Referring to Figures 1 to 7, this application embodiment provides a button cell 10, which includes a casing 20 and a stacked cell 30. The casing 20 includes a bottom shell 21, terminals 22, and a top cover 23. The top cover 23 is sealed to the bottom shell 21. The terminals 22 are connected to the top cover 23. The stacked cell 30 is disposed within the casing 20. Along the stacking direction X of the stacked cell 30, the stacked cell 30 includes a first single-sided electrode 31 and a second single-sided electrode 32 located on the outermost side. The first single-sided electrode 31 and the second single-sided electrode 32 have opposite polarities. The first single-sided electrode 31 includes a first current collector 311 and a first active material layer 312. Along the stacking direction X of the stacked cell 30, the surface of the first current collector 311 facing the terminal 22 is directly electrically connected to the terminal 22. The first active material layer 312 is disposed on the surface of the first current collector 311 facing away from the terminal 22. The second single-sided electrode 32 includes a second current collector 321 and a second active material layer 322. The surface of the second current collector 321 facing away from the electrode post 22 is directly electrically connected to the bottom shell 21. The second active material layer 322 is disposed on the surface of the second current collector 321 facing the electrode post 22.

[0089] In this embodiment, referring to Figure 4, the outer casing 20 can provide protection for the stacked battery cell 30. The bottom casing 21 may include a receiving space. The stacked battery cell 30 is disposed within the receiving space. The stacking direction X of the stacked battery cell 30 may be the same as the depth direction of the receiving space. In some implementations, along the stacking direction X of the stacked battery cell 30, the bottom wall 211 of the bottom casing 21 is correspondingly disposed with the top cover 23. The surface of the second current collector 321 facing away from the electrode post 22 is directly electrically connected to the bottom wall 211. In some implementations, the stacked battery cell 30 includes a separator 35. The stacking direction X of the stacked battery cell 30 may refer to the direction in which the electrode and the separator 35 are stacked together.

[0090] In this embodiment of the application, referring to Figures 4 and 7, the first single-sided electrode 31 and the second single-sided electrode 32 are arranged opposite to each other. Each of the first single-sided electrode 31 and the second single-sided electrode 32 includes a first current collector 311 and a second current collector 321. The first current collector 311 and the second current collector 321 are directly electrically connected to the terminal post 22 and the bottom shell 21, respectively, so that the terminal post 22 and the outer shell 20 can respectively serve as two electrodes of the button battery 10. The direct electrical connection between the first current collector 311 and the terminal post 22 means that the first current collector 311 does not require an additional adapter structure to be electrically connected to the terminal post 22. The direct electrical connection between the second current collector 321 and the bottom shell 21 means that the second current collector 321 does not require an additional adapter structure to be electrically connected to the bottom shell 21.

[0091] In this embodiment, the first single-sided electrode 31 refers to the first active material layer 312 being disposed on only one surface of the first current collector 311 facing away from the electrode post 22. The second single-sided electrode 32 refers to the second active material layer 322 being disposed on only one surface of the second current collector 321 facing the electrode post 22.

[0092] The button cell 10 of this embodiment includes a casing 20 and stacked cells 30 disposed within the casing 20. The outermost first single-sided electrode 31 and second single-sided electrode 32 of the stacked cells 30 are directly electrically connected to the terminal post 22 and the bottom shell 21, respectively, eliminating the need for an additional adapter plate between the stacked cells 30 and the casing 20. In the stacking direction X of the stacked cells 30, no space is required between the stacked cells 30 and the casing 20 to avoid the adapter plate, thereby improving the structural compactness of the button cell 10 in the stacking direction X. This structural design helps to reduce the overall size of the button cell 10 in the stacking direction X, thereby reducing the overall volume of the button cell 10 and thus improving its energy density.

[0093] In addition, in related technologies, button batteries include wound cells. Wound cells are cells formed by winding electrodes and separators with opposite polarities. Wound cells have a cylindrical structure, which has limited applicability. The button battery 10 of this application embodiment includes a stacked cell 30. The structural form of the stacked cell 30 is related to the shape of the electrodes and separator 35. According to the shape design requirements of the button battery 10, the electrodes and separator 35 can be relatively easily shaped so that the shape of the stacked cell 30 matches the shape of the casing 20. Therefore, the shape of the stacked cell 30 is not limited to a circle, but can also be other non-circular structures. This can help improve the applicability of the structural form of the stacked cell 30. In addition, the stacked cell 30 has a higher space utilization rate than the wound cell, and it is easier to manufacture the first single-sided electrode 31 or the second single-sided electrode 32 for direct electrical connection with the terminal post 22 or the bottom casing 21.

[0094] In some possible implementations, referring to Figures 4 and 7, the button cell 10 includes a first adhesive member 40. The first adhesive member 40 bonds the first current collector 311 to the terminal post 22, which helps reduce the difficulty of connecting the first current collector 311 and the terminal post 22. The first adhesive member 40 connects the terminal post 22 and the first current collector 311. The first adhesive member 40 can fix the position of the stacked cell 30 within the housing 20, reducing the possibility of the stacked cell 30 shifting within the housing 20, causing the terminal post 22 and the first current collector 311 to lose their electrical connection. Exemplarily, the first adhesive member 40 can be formed of an adhesive, for example, the first adhesive member 40 can be an adhesive glue.

[0095] For example, the first adhesive 40 may be an insulating adhesive. The first adhesive 40 itself is not conductive. For instance, the first adhesive 40 may be an adhesive with insulating properties.

[0096] For example, the first adhesive 40 can be a pressure-sensitive adhesive. The first adhesive 40 does not require heating, solvent activation or complex curing processes. It can be bonded by applying relatively small pressure to the first adhesive 40 by the pole 22 and the first current collector 311, which reduces the difficulty of connection.

[0097] For example, the first adhesive 40 can be a conductive adhesive. The first adhesive 40 itself has electrical conductivity, so that the electrode 22 and the first current collector 311 can also be electrically connected through the first adhesive 40. For example, the first adhesive 40 can be a conductive adhesive.

[0098] In some possible implementations, referring to Figure 8, the electrode post 22 includes a first wall surface 22a and a first protrusion 201. The first wall surface 22a faces the laminated cell 30, and the first protrusion 201 protrudes from the first wall surface 22a. The first protrusion 201 abuts against the surface of the first current collector 311 facing the electrode post 22 to achieve an electrical connection between the electrode post 22 and the first current collector 311. Along the stacking direction X of the laminated cell 30, there is a first gap L1 between the first wall surface 22a and the first current collector 311. The first protrusion 201 abutting against the first current collector 311 means that the first protrusion 201 and the first current collector 311 are in direct contact and have compressive stress on each other. By directly contacting the first protrusion 201 with the first current collector 311, on the one hand, it helps to reduce the difficulty of achieving electrical connection between the terminal 22 and the first current collector 311. On the other hand, it helps to ensure that the terminal 22 and the first current collector 311 maintain a stable electrical connection in the assembled button battery 10, reducing the possibility of poor contact problems such as intermittent connection between the terminal 22 and the first current collector 311.

[0099] In some examples, the first spacing L1 ranges from greater than 0 micrometers (μm) to less than or equal to 50 micrometers.

[0100] In some examples, referring to Figures 3 and 4, the top cover 23 and the bottom cover 21 can be directly electrically connected. The housing 20 includes an insulator 24. The insulator 24 connects the terminal post 22 and the top cover 23. The terminal post 22 and the top cover 23 are insulated from each other by the insulator 24. The terminal post 22 and the top cover 23 are in a non-electrically connected state. Exemplarily, the insulator 24 can be an insulating adhesive. For example, the insulator 24 can be an insulating adhesive. The insulator 24 bonds the terminal post 22 and the top cover 23 to secure the terminal post 22 to the top cover 23.

[0101] In some examples, referring to Figures 4 and 8, the top cover 23 includes a central through-hole 231. The pole post 22 includes a base 221 and a boss 222. The base 221 is connected to the top cover 23. The boss 222 is correspondingly disposed with respect to the central through-hole 231. An insulating member 24 is disposed between the base 221 and the top cover 23. The surface of the first current collector 311 facing the pole post 22 is directly electrically connected to the base 221. A first protrusion 201 may be disposed on the base 221.

[0102] For example, referring to FIG8, a first adhesive member 40 is disposed between the terminal post 22 and the first current collector 311. The first adhesive member 40 has a first clearance channel 100. The terminal post 22 includes a first protrusion 201. The first protrusion 201 passes through the first clearance channel 100 and abuts against the first current collector 311. The first clearance channel 100 is used to avoid the first protrusion 201, reducing the possibility that the first adhesive member 40 is located between the first protrusion 201 and the first current collector 311 and affects the electrical connection state of the first protrusion 201 and the first current collector 311. Electrolyte can be filled into the casing 20 of the button battery 10. The first protrusion 201 can be surrounded by the first adhesive 40, so that the first adhesive 40 can prevent the electrolyte from wetting the connection area between the first protrusion 201 and the first current collector 311, reducing the possibility that the first protrusion 201 and the first current collector 311 will be corroded in the connection area, resulting in an unstable electrical connection between the first protrusion 201 and the first current collector 311.

[0103] For example, the first protrusion 201 may be a shape such as a cone or a semi-circle, with the top being narrower than the bottom, making it easier for the first protrusion 201 to pass through the first adhesive member 40.

[0104] In some possible implementations, referring to Figure 9, the terminal post 22 includes a first wall surface 22a and a first recess 22b. The first wall surface 22a is disposed facing the laminated cell 30. The first recess 22b includes an opening located in the first wall surface 22a. A first adhesive member 40 is disposed within the first recess 22b. The first wall surface 22a abuts against the surface of the first current collector 311 facing the terminal post 22. The first adhesive member 40 bonds the first current collector 311 to the terminal post 22.

[0105] The first wall surface 22a of the terminal post 22 is in direct contact with the surface of the first current collector 311 facing the terminal post 22. The distance between the first wall surface 22a and the first current collector 311 is zero. The above structural design is beneficial to reducing the overall size of the button cell 10 in the stacking direction X of the stacked cells 30, thereby reducing the overall volume of the button cell 10 and thus improving the energy density of the button cell 10.

[0106] In some examples, there may be multiple first recesses 22b. Each first recess 22b is provided with a first adhesive member 40.

[0107] In some feasible implementations, as shown in Figures 5 and 7, the first current collector 311 includes a first tab 3111 and a first body portion 3112 connected together. The first tab 3111 and the first body portion 3112 are integrally formed. A first active material layer 312 is disposed on the first body portion 3112. The surface of the first body portion 3112 facing the electrode post 22 does not have the first active material layer 312 disposed thereon. The surface of the first body portion 3112 facing the electrode post 22 is directly electrically connected to the electrode post 22. The first tab 3111 does not have the first active material layer 312 disposed thereon. In the laminated cell 30, the first single-sided electrode 31 can be electrically connected to other electrodes of the same polarity through the first tab 3111. The first single-sided electrode 31 is located on the outermost side of the entire laminated cell 30.

[0108] The method by which the stacked cell 30 is electrically connected to the terminal post 22 through the first main body 3112 can reduce the spacing between the stacked cell 30 and the terminal post 22 in the stacking direction X, thereby reducing the overall size of the button cell 10 in the stacking direction X and thus reducing the overall volume of the button cell 10, which in turn helps to improve the energy density of the button cell 10. The relatively large area of ​​the first main body 3112 itself helps to reduce the difficulty of achieving electrical connection between the first current collector 311 and the terminal post 22.

[0109] In some examples, referring to Figures 4 and 7, the button battery 10 includes a first adhesive member 40. The first adhesive member 40 is disposed between the terminal post 22 and the first main body portion 3112. The first adhesive member 40 bonds the first main body portion 3112 to the terminal post 22. The first main body portion 3112 itself has a relatively large area. Using the first adhesive member 40 to bond the first main body portion 3112 to the terminal post 22 helps reduce the connection difficulty between the first adhesive member 40 and the first current collector 311, and also helps increase the connection area between the first current collector 311 and the terminal post 22, thereby improving the connection stability between the first current collector 311 and the terminal post 22.

[0110] In some examples, the pole post 22 includes a first protrusion 201. The first protrusion 201 abuts against the surface of the first body portion 3112 facing the pole post 22 to achieve an electrical connection between the pole post 22 and the first current collector 311.

[0111] In some examples, the pole post 22 includes a first wall surface 22a. The first wall surface 22a abuts against the surface of the first body portion 3112 facing the pole post 22 to achieve an electrical connection between the pole post 22 and the first current collector 311.

[0112] In some examples, the surface area of ​​the electrode post 22 facing the laminated cell 30 is greater than or equal to the area of ​​the first main body portion 3112. The electrode post 22 can cover the entire first main body portion 3112. In the event of expansion of the laminated cell 30, the electrode post 22 can provide overall support for the first main body portion 3112 and apply a reaction force to the first main body portion 3112. This can promote uniform stress distribution on the first main body portion 3112, reduce the possibility of stress concentration areas caused by uneven stress distribution on the first main body portion 3112, and prevent the first active material layer 312 from peeling off or falling off from the first main body portion 3112 in stress concentration areas.

[0113] In some feasible embodiments, as shown in Figures 10, 11, and 12, the first current collector 311 includes a first tab 3111, a first main body portion 3112, and a first folded portion 3113 connected together. The first tab 3111, the first main body portion 3112, and the first folded portion 3113 are integrally formed. A first active material layer 312 is disposed on the first main body portion 3112. The first folded portion 3113 is folded relative to the first main body portion 3112. The first folded portion 3113 is located between the first main body portion 3112 and the electrode post 22. The surface of the first folded portion 3113 facing the electrode post 22 is directly electrically connected to the electrode post 22.

[0114] The surface of the first main body 3112 facing the electrode post 22 does not have a first active material layer 312. Neither the first electrode tab 3111 nor the first folded portion 3113 has a first active material layer 312. Both the first electrode tab 3111 and the first folded portion 3113 are empty foil areas. The first electrode tab 3111 and the first folded portion 3113 are connected to different positions on the first main body 3112. The first single-sided electrode 31 can be electrically connected to other electrodes of the same polarity through the first electrode tab 3111. The first current collector 311 is directly electrically connected to the electrode post 22 through the first folded portion 3113.

[0115] Referring to Figure 13, after the laminated cell 30 is installed into the bottom housing 21, the first folded portion 3113 located outside the bottom housing 21 is connected to the terminal post 22, and then the terminal post 22 and the top cover 23 are closed onto the bottom housing 21. During the closing process, the first folded portion 3113 folds towards the first main body portion 3112. The closed top cover 23 and the bottom housing 21 are connected, and the first folded portion 3113 is located between the terminal post 22 and the first main body portion 3112.

[0116] The first current collector 311 is provided with a first folding part 3113, which can realize the operation of first connecting and fixing the stacked cell 30 to the terminal post 22, and then closing the top cover 23. This helps to reduce the connection difficulty between the stacked cell 30 and the terminal post 22, and improve the connection stability and connection efficiency between the stacked cell 30 and the terminal post 22.

[0117] When the first current collector 311 is directly electrically connected to the terminal 22 via the first main body 3112, after the laminated cell 30 is installed into the housing, the top cover 23 with the terminal 22 is closed onto the bottom housing 21. Assuming the connection position between the top cover 23 and the bottom housing 21 is in a predetermined position, the terminal 22 can abut against the first current collector 311, ensuring a good electrical connection between them. If the connection position between the top cover 23 and the bottom housing 21 deviates, there is a possibility that the terminal 22 may not abut against the first main body 3112, resulting in a non-electrical connection between the terminal 22 and the first main body 3112. When the first current collector 311 is directly electrically connected to the terminal 22 via the first main body 3112, the accuracy requirement for the connection position of the top cover 23 and the bottom housing 21 is relatively high.

[0118] The first current collector 311 is provided with a first folding part 3113. The position of the first folding part 3113 can be flexibly adjusted. The first folding part 3113 is first connected to the pole post 22, and then connected to the top cover 23 and the bottom shell 21. Therefore, the connection position between the top cover 23 and the bottom shell 21 will not affect the connection state between the first current collector 311 and the pole post 22. This helps to reduce the possibility of the above-mentioned problems and reduce the accuracy requirements of the connection position between the top cover 23 and the bottom shell 21.

[0119] In some examples, the surface of the first folded portion 3113 facing away from the pole post 22 and the surface of the first main body portion 3112 facing the pole post 22 can be in contact with each other, so as to reduce the space occupied by the stacked cell 30 in the stacking direction X of the stacked cell 30 and improve the structural compactness of the stacked cell 30.

[0120] In some examples, the first folding portion 3113 is welded to the terminal post 22. The connection between the first current collector 311 and the terminal post 22 via the first folding portion 3113 facilitates the welding operation between the first folding portion 3113 and the terminal post 22. The first folding portion 3113, located outside the bottom shell 21, can be pre-fixed to the terminal post 22 in relative position, and then welded to one side of the first folding portion 3113 and the terminal post 22, reducing the difficulty of connecting the first folding portion 3113 and the terminal post 22. Welding the first folding portion 3113 and the terminal post 22 improves the connection strength and stability between them, reducing the possibility of the first folding portion 3113 and the terminal post 22 becoming disconnected during use of the button battery 10.

[0121] For example, laser welding can be used to weld the first folded portion 3113 and the electrode post 22. The thickness of the electrode post 22 is greater than the thickness of the first folded portion 3113. Laser cannot melt-weld the first folded portion 3113 and the electrode post 22 from one side of the electrode post 22. Since the first current collector 311 is connected to the electrode post 22 via the first folded portion 3113, laser welding can be used to weld the first folded portion 3113 and the electrode post 22 from one side of the first folded portion 3113, reducing the difficulty of connecting the first folded portion 3113 and the electrode post 22.

[0122] In some examples, the first folded portion 3113 is bonded to the pole post 22. Bonding the first current collector 311 to the pole post 22 via the first folded portion 3113 reduces the difficulty of connecting the first folded portion 3113 and the pole post 22, facilitates observation and inspection of the bonding state, and eliminates concerns about over-welding, incomplete welding, or weld marks. After ensuring the bonding state between the first folded portion 3113 and the pole post 22 meets the requirements, the top cover 23 with the pole post 22 is then sealed to the bottom shell 21.

[0123] Exemplarily, the first folded portion 3113 and the pole post 22 can be bonded together using a first adhesive 40. Exemplarily, the first adhesive 40 can be formed of an adhesive, for example, the first adhesive 40 can be an adhesive glue. Exemplarily, the first adhesive 40 can cover the surface of the first folded portion 3113 facing the pole post 22.

[0124] In some examples, the pole post 22 includes a first protrusion 201. The first protrusion 201 abuts against the surface of the first fold 3113 facing the pole post 22 to achieve an electrical connection between the pole post 22 and the first current collector 311.

[0125] In some examples, the pole post 22 includes a first wall surface 22a. The first wall surface 22a abuts against the surface of the first fold 3113 facing the pole post 22 to achieve an electrical connection between the pole post 22 and the first current collector 311.

[0126] In some examples, the area of ​​the first folded portion 3113 is greater than or equal to the area of ​​the first main body portion 3112. The first folded portion 3113 can cover the entire first main body portion 3112. When the laminated cell 30 expands, and the first main body portion 3112 comes into contact with the first folded portion 3113, the first folded portion 3113 can provide overall support for the first main body portion 3112 and apply a reaction force to the first main body portion 3112. This can help to ensure uniform stress distribution on the first main body portion 3112, reduce the possibility of stress concentration areas caused by uneven stress distribution on the first main body portion 3112, and prevent the first active material layer 312 from peeling off or falling off from the first main body portion 3112 in stress concentration areas.

[0127] For example, the shape and size of the first folding portion 3113 are the same as the shape and size of the first main body portion 3112.

[0128] For example, the surface area of ​​the electrode post 22 facing the laminated cell 30 can be greater than or equal to the area of ​​the first folded portion 3113. The electrode post 22 can cover the entire first folded portion 3113. When the laminated cell 30 expands, the electrode post 22 and the first folded portion 3113 can simultaneously support the first main body portion 3112 as a whole and apply a reaction force to the first main body portion 3112 as a whole. This can help to ensure uniform stress distribution on the first main body portion 3112, reduce the possibility of stress concentration areas caused by uneven stress distribution on the first main body portion 3112, and prevent the first active material layer 312 from peeling off or falling off from the first main body portion 3112 in the stress concentration areas.

[0129] In some possible implementations, the bottom casing 21 has a bottom wall 211. The button cell 10 includes a second adhesive member 50. The second adhesive member 50 bonds the second current collector 321 to the bottom wall 211, which helps to reduce the difficulty of connecting the second current collector 321 and the bottom wall 211. The second adhesive member 50 connects the bottom wall 211 and the second current collector 321. The second adhesive member 50 can fix the position of the stacked cell 30 within the casing 20, reducing the possibility that the stacked cell 30 may shake within the casing 20, causing the bottom wall 211 and the second current collector 321 to lose their electrical connection.

[0130] For example, the second adhesive 50 may be formed of an adhesive, such as adhesive glue.

[0131] For example, the second adhesive 50 may be an insulating adhesive. The second adhesive 50 itself is not conductive. For instance, the second adhesive 50 may be an adhesive with insulating properties.

[0132] For example, the second adhesive 50 can be a pressure-sensitive adhesive. The second adhesive 50 does not require heating, solvent activation or complex curing processes. It can be bonded by applying relatively small pressure to the second current collector 321 and the bottom wall 211, which reduces the difficulty of connection.

[0133] For example, the second adhesive 50 can be a conductive adhesive. The second adhesive 50 itself is conductive, so that the bottom shell 21 and the second current collector 321 can also be electrically connected through the second adhesive 50. For example, the second adhesive 50 can be a conductive adhesive.

[0134] In some possible implementations, referring to Figure 14, the bottom wall 211 has a second wall surface 21a. The bottom shell 21 includes a second protrusion 202. The second protrusion 202 is provided on the bottom wall 211. The second wall surface 21a faces the stacked cell 30. The second protrusion 202 protrudes from the second wall surface 21a. The second protrusion 202 abuts against the surface of the second current collector 321 facing the bottom wall 211 to achieve an electrical connection between the bottom shell 21 and the second current collector 321. Along the stacking direction X of the stacked cell 30, there is a second distance L2 between the second wall surface 21a and the second current collector 321. The second protrusion 202 abutting against the second current collector 321 means that the second protrusion 202 and the second current collector 321 are in direct contact and have compressive stress between them. By directly contacting the second protrusion 202 with the second current collector 321, on the one hand, it helps to reduce the difficulty of achieving electrical connection between the bottom shell 21 and the second current collector 321. On the other hand, it helps to ensure that the bottom shell 21 and the second current collector 321 maintain a stable electrical connection in the assembled button battery 10, reducing the possibility of poor contact problems such as loose connection between the bottom shell 21 and the second current collector 321.

[0135] In some examples, the second spacing L2 ranges from greater than 0 micrometers (μm) to less than or equal to 50 micrometers.

[0136] For example, the second adhesive 50 is disposed between the bottom wall 211 and the second current collector 321. The second adhesive 50 has a second clearance channel 110. A second protrusion 202 is provided on the bottom wall 211. The second protrusion 202 passes through the second clearance channel 110 and abuts against the second current collector 321. The second clearance channel 110 is used to avoid the second protrusion 202, reducing the possibility that the second adhesive 50 is located between the second protrusion 202 and the second current collector 321 and affects the electrical connection state of the second protrusion 202 and the second current collector 321. Electrolyte can be filled into the casing 20 of the button battery 10. The second adhesive 50 can surround the second protrusion 202, so that the second adhesive 50 can prevent the electrolyte from wetting the connection area between the second protrusion 202 and the second current collector 321, reducing the possibility that corrosion of the second protrusion 202 and the second current collector 321 in the connection area will cause instability in the electrical connection state of the second protrusion 202 and the second current collector 321.

[0137] For example, the second protrusion 202 may be a shape such as a cone or a semi-circle, with the top being narrower than the bottom, making it easier for the second protrusion 202 to pass through the second adhesive member 50.

[0138] In some possible implementations, referring to Figure 15, the bottom wall 211 has a second wall surface 21a and a second recess 21b. The second wall surface 21a faces the laminated cell 30. The second recess 21b includes an opening located in the second wall surface 21a. A second adhesive member 50 is disposed within the second recess 21b, and the second wall surface 21a abuts against the surface of the second current collector 321 facing the bottom wall 211. The second adhesive member 50 bonds the second current collector 321 to the terminal post 22.

[0139] The second wall surface 21a is in direct contact with the surface of the second current collector 321 facing the bottom wall 211. The distance between the second wall surface 21a and the second current collector 321 is zero. The above structural design is beneficial to reducing the overall size of the button cell 10 in the stacking direction X of the stacked cells 30, thereby reducing the overall volume of the button cell 10 and thus improving the energy density of the button cell 10.

[0140] In some examples, there may be multiple second recesses 21b. Each second recess 21b is provided with a second adhesive member 50.

[0141] In some possible implementations, as shown in Figures 6 and 7, the second current collector 321 includes a connected second tab 3211 and a second body portion 3212. The second tab 3211 and the second body portion 3212 are integrally formed. A second active material layer 322 is disposed on the second body portion 3212. The surface of the second body portion 3212 facing away from the electrode post 22 is directly electrically connected to the bottom shell 21.

[0142] The second active material layer 322 is not provided on the surface of the second main body 3212 facing the bottom wall 211. The bottom shell 21 may include the bottom wall 211. The surface of the second main body 3212 facing the bottom wall 211 can be directly electrically connected to the bottom wall 211. The second active material layer 322 is not provided on the second tab 3211. In the laminated cell 30, the second single-sided electrode 32 can be electrically connected to other electrodes of the same polarity through the second tab 3211. The second single-sided electrode 32 is located on the outermost side of the entire laminated cell 30.

[0143] The method by which the stacked cell 30 is electrically connected to the bottom shell 21 through the second main body 3212 can help reduce the spacing between the stacked cell 30 and the bottom shell 21 in the stacking direction X, thereby reducing the overall size of the button cell 10 in the stacking direction X and thus reducing the overall volume of the button cell 10, which in turn helps to improve the energy density of the button cell 10. The relatively large area of ​​the second main body 3212 itself helps to reduce the difficulty of achieving electrical connection between the second current collector 321 and the bottom shell 21.

[0144] In some examples, as shown in Figures 4 and 7, the button battery 10 includes a second adhesive member 50. The second adhesive member 50 is disposed between the bottom wall 211 and the second main body portion 3212. The second adhesive member 50 bonds the second main body portion 3212 to the bottom wall 211. The second main body portion 3212 itself has a relatively large area. Using the second adhesive member 50 to bond the second main body portion 3212 to the bottom wall 211 helps reduce the connection difficulty between the second adhesive member 50 and the second current collector 321, and also helps increase the connection area between the second current collector 321 and the bottom wall 211, thereby improving the connection stability between the second current collector 321 and the bottom wall 211.

[0145] In some examples, the bottom shell 21 includes a second protrusion 202. The second protrusion 202 abuts against the surface of the second body portion 3212 facing the bottom wall 211 to achieve an electrical connection between the bottom wall 211 and the second current collector 321.

[0146] In some examples, the bottom wall 211 has a second wall surface 21a. The second wall surface 21a abuts against the surface of the second body portion 3212 facing the bottom wall 211 to achieve an electrical connection between the bottom wall 211 and the second current collector 321.

[0147] In some examples, referring to Figures 12 and 16, the second current collector 321 includes a connected second tab 3211, a second main body portion 3212, and a second folded portion 3213. The second tab 3211, the second main body portion 3212, and the second folded portion 3213 are integrally formed. A second active material layer 322 is disposed on the second main body portion 3212. The second folded portion 3213 is folded relative to the second main body portion 3212. The second folded portion 3213 is located between the second main body portion 3212 and the bottom shell 21. The surface of the second folded portion 3213 facing away from the electrode post 22 is directly electrically connected to the bottom shell 21.

[0148] The surface of the second main body 3212 facing the bottom shell 21 does not have a second active material layer 322. Neither the second electrode tab 3211 nor the second folded portion 3213 has a second active material layer 322. Both the second electrode tab 3211 and the second folded portion 3213 are empty foil areas. The second electrode tab 3211 and the second folded portion 3213 are connected to different positions on the second main body 3212. The second single-sided electrode 32 can be electrically connected to other electrodes of the same polarity via the second electrode tab 3211. The second current collector 321 is directly electrically connected to the bottom shell 21 via the second folded portion 3213.

[0149] Before the laminated cell 30 is installed into the bottom housing 21, the second folding portion 3213 can be connected to the bottom housing 21. Then, the other parts of the laminated cell 30 are installed into the bottom housing 21, and the terminal post 22 and the top cover 23 are then closed onto the bottom housing 21. During the process of installing the other parts of the laminated cell 30 into the bottom housing 21, the second folding portion 3213 folds relative to the second main body portion 3212. After the laminated cell 30 is installed into the bottom housing 21, the second folding portion 3213 is located between the bottom housing 21 and the second main body portion 3212.

[0150] By providing a second folding part 3213 in the second current collector 321, the stacked battery cell 30 can be first connected and fixed to the bottom wall 211, and then the stacked battery cell 30 can be installed into the bottom shell 21. This helps to reduce the connection difficulty between the stacked battery cell 30 and the bottom shell 21, and improve the connection stability and connection efficiency between the stacked battery cell 30 and the bottom shell 21.

[0151] In some examples, the surface of the second folded portion 3213 facing away from the bottom wall 211 and the surface of the second main body portion 3212 facing the bottom wall 211 can contact each other to reduce the space occupied by the stacked cell 30 in the stacking direction X of the stacked cell 30 and improve the structural compactness of the stacked cell 30.

[0152] In some examples, the bottom shell 21 has a bottom wall 211. The second folded portion 3213 is welded to the bottom wall 211. The second current collector 321 is connected to the bottom wall 211 by the second folded portion 3213, which facilitates the welding operation between the second folded portion 3213 and the bottom wall 211. The second folded portion 3213 located inside the bottom shell 21 is first fixed in relative position to the bottom wall 211, and then the second folded portion 3213 and the bottom wall 211 are welded on one side, reducing the difficulty of connecting the second folded portion 3213 and the bottom wall 211. The welding method used to connect the second folded portion 3213 and the bottom wall 211 helps to improve the connection strength and stability between the second folded portion 3213 and the bottom wall 211, and reduces the possibility of the second folded portion 3213 and the bottom wall 211 becoming disconnected during the use of the button battery 10.

[0153] For example, laser welding can be used to weld the second folded portion 3213 and the bottom wall 211. The thickness of the bottom shell 21 is greater than the thickness of the second folded portion 3213. Laser cannot perform fusion welding on the second folded portion 3213 and the bottom wall 211 from the outside of the bottom shell 21. Since the second current collector 321 is connected to the bottom wall 211 via the second folded portion 3213, laser welding can be used on one side of the second folded portion 3213 to weld the second folded portion 3213 and the bottom wall 211, reducing the difficulty of connecting the second folded portion 3213 and the bottom wall 211.

[0154] In some examples, the second folded portion 3213 is bonded to the bottom wall 211. Bonding the second current collector 321 to the bottom wall 211 via the second folded portion 3213 reduces the difficulty of connection between the second folded portion 3213 and the bottom wall 211, facilitates observation and inspection of the bonding state, and eliminates concerns about over-soldering, incomplete soldering, or solder marks. After ensuring the bonding state between the second folded portion 3213 and the bottom wall 211 meets the requirements, the remaining parts of the laminated cell 30 are then installed into the bottom housing 21, and finally the top cover 23 is closed onto the bottom housing 21, and the top cover 23 and the bottom housing 21 are connected.

[0155] Exemplarily, the second fold 3213 and the bottom wall 211 can be bonded together using a second adhesive 50. Exemplarily, the second adhesive 50 can be formed of an adhesive, for example, the second adhesive 50 can be an adhesive glue. Exemplarily, the second adhesive 50 can cover the surface of the second fold 3213 facing the bottom wall 211.

[0156] In some examples, the bottom shell 21 includes a second protrusion 202. The second protrusion 202 abuts against the surface of the second fold 3213 facing the bottom wall 211 to achieve an electrical connection between the bottom wall 211 and the second current collector 321.

[0157] In some examples, the bottom wall 211 has a second wall surface 21a. The second wall surface 21a abuts against the surface of the second fold 3213 facing the bottom wall 211 to achieve an electrical connection between the bottom wall 211 and the second current collector 321.

[0158] In some examples, the area of ​​the second folded portion 3213 is greater than or equal to the area of ​​the second main body portion 3212. The second folded portion 3213 can cover the entire second main body portion 3212. When the laminated cell 30 expands, and the second main body portion 3212 comes into contact with the second folded portion 3213, the second folded portion 3213 can provide support for the second main body portion 3212 and apply a reaction force to the second main body portion 3212 as a whole. This can help to ensure uniform stress distribution on the second main body portion 3212, reduce the possibility of stress concentration areas caused by uneven stress distribution on the second main body portion 3212, and prevent the second active material layer 322 from peeling off or falling off from the second main body portion 3212 in stress concentration areas.

[0159] For example, the shape and size of the second folding portion 3213 are the same as the shape and size of the second main body portion 3212.

[0160] In some feasible implementations, as shown in Figures 7, 17, and 18, the laminated cell 30 includes a first double-sided electrode 33 and a second double-sided electrode 34. Alternating layers of the first double-sided electrode 33 and the second double-sided electrode 34 are disposed between a first single-sided electrode 31 and a second single-sided electrode 32. The first single-sided electrode 31 and the first double-sided electrode 33 have the same polarity. The first single-sided electrode 31 and each of the first double-sided electrode 33 are electrically connected. The second single-sided electrode 32 and the second double-sided electrode 34 have the same polarity. The second single-sided electrode 32 and each of the second double-sided electrode 34 are electrically connected.

[0161] In this embodiment, the first double-sided electrode 33 refers to an electrode with an active material layer on both opposite surfaces of the current collector. The second double-sided electrode 34 refers to an electrode with an active material layer on both opposite surfaces of the current collector.

[0162] A first single-sided electrode 31, a second double-sided electrode 34, a first double-sided electrode 33, and a second single-sided electrode 32 are stacked along the stacking direction X. The electrode adjacent to the first single-sided electrode 31 is the second double-sided electrode 34. A separator 35 may be disposed between the first single-sided electrode 31 and the second double-sided electrode 34. The electrode adjacent to the second single-sided electrode 32 is the first double-sided electrode 33. A separator 35 may be disposed between the second single-sided electrode 32 and the first double-sided electrode 33. A separator 35 may be disposed between the first double-sided electrode 33 and the second double-sided electrode 34.

[0163] In some examples, as shown in Figures 2, 3, and 4, the first tab 3111 and the third tab 331 converge toward the bottom wall 211 and then fold back toward the top cover 23, forming a two-section structure. Welded sections are formed on the folded areas of the first tab 3111 and the third tab 331 toward the top cover 23. This structural design results in the first tab 3111 and the third tab 331 occupying a relatively large space.

[0164] Referring to Figures 7, 17, and 18, the first single-sided electrode 31 includes a first tab 3111. The first double-sided electrode 33 includes a third tab 331. The first tab 3111 and each of the third tabs 331 are brought together along the stacking direction X of the stacked cells 30. They can be brought together towards the bottom wall 211 of the bottom shell 21 or towards the top cover 23 and welded together to form a first gathered portion 60. The first gathered portion 60 is a single-section structure. That is, the first tab 3111 and the third tab 331 are brought together and welded towards the bottom wall 211 or the top cover 23. The first tab 3111 and the third tab 331 do not need to be brought together towards the bottom wall 211 or the top cover 23 and then folded in the opposite direction. This helps to reduce the space occupied by the first tab 3111 and the third tab 331, and helps to reduce the overall size of the button cell 10, thereby reducing the overall volume of the button cell 10 and thus helping to improve the energy density of the button cell 10. The first tab 3111 and the third tab 331, when folded together and then folded over once, can be called a two-segment structure. Folding them over once more creates a three-segment structure.

[0165] The bottom shell 21 includes a side wall 212. The bottom wall 211 is connected to the side wall 212 to form a connection. A first folding portion 60 is located near the connection between the bottom wall 211 and the side wall 212.

[0166] In some examples, as shown in Figures 2, 3, and 4, the second tab 3211 and the fourth tab 341 are folded towards the bottom wall 211 and then folded back towards the top cover 23, forming a two-section structure. Welded portions are formed on the folded areas of the second tab 3211 and the fourth tab 341 towards the top cover 23. This structural design results in the second tab 3211 and the fourth tab 341 occupying a relatively large space. This application, by connecting the uppermost single-sided electrode to the pole post 22 and the lowermost single-sided electrode to the bottom shell 21, eliminates the need for an adapter. In the prior art, the folded welded portion needs to be reconnected to the adapter, thus requiring a larger welded portion. In this application, the folded portion can be directly cut, allowing it to be closer to the bottom wall 211 or the top cover 23 without secondary folding, significantly improving the space utilization of the battery cell.

[0167] Referring to Figures 7, 17, and 19, the second single-sided electrode 32 includes a second tab 3211. The second double-sided electrode 34 includes a fourth tab 341. The second tab 3211 and each of the fourth tabs 341 can be gathered together along the stacking direction X of the stacked cells 30, either by being gathered and welded towards the bottom wall 211 or by being gathered and welded towards the top cover 23 to form a second gathered portion 70. The second gathered portion 70 is a single-section structure. The second tab 3211 and the fourth tab 341 are gathered and welded towards the top cover 23 or the bottom wall 211. The second tab 3211 and the fourth tab 341 do not need to be gathered towards the bottom wall 211 or the top cover 23 and then folded in the opposite direction, which helps to reduce the space occupied by the second tab 3211 and the fourth tab 341, and helps to reduce the overall size of the button cell 10, thereby reducing the overall volume of the button cell 10 and thus helping to improve the energy density of the button cell 10. The second tab 3211 and the fourth tab 341, when folded together and then folded over once, can be called a two-segment structure. Folding them over once more creates a three-segment structure.

[0168] The bottom shell 21 includes a side wall 212. The bottom wall 211 is connected to the side wall 212 to form a connecting portion. The second folding portion 70 is located near the connecting portion between the bottom wall 211 and the side wall 212.

[0169] In some feasible implementations, the first single-sided electrode 31 is a cathode electrode. The electrode post 22 may be made of aluminum or an aluminum alloy. The second single-sided electrode 32 is an anode electrode. The bottom shell 21 may be made of stainless steel. The top cover 23 may be made of stainless steel. The outer edge of the top cover 23 and the top of the bottom shell 21 are welded and sealed. Referring to Figure 18 or Figure 20, after the first electrode tab 3111 and each of the third electrode tabs 331 are folded and welded together, insulating tape 80 can be attached to the outside of the first electrode tab 3111 and the third electrode tab 331. The insulating tape 80 can insulate and isolate the first electrode tab 3111 and the third electrode tab 331 from the bottom shell 21 respectively, reducing the possibility of electrical connection between the first electrode tab 3111 and the third electrode tab 331 and the bottom shell 21.

[0170] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A button battery, characterized in that, include: The outer casing includes a bottom shell, a terminal post, and a top cover. The top cover is sealed to the bottom shell, the terminal post is connected to the top cover, and the bottom shell and the terminal post have different polarities. A laminated battery cell is disposed within the housing. Along the stacking direction of the laminated battery cell, the laminated battery cell includes a first single-sided electrode and a second single-sided electrode located on the outermost side. The first single-sided electrode and the second single-sided electrode have opposite polarities. The first single-sided electrode includes a first current collector and a first active material layer. Along the stacking direction of the laminated battery cell, the surface of the first current collector facing the electrode post is directly electrically connected to the electrode post. The first active material layer is disposed on the surface of the first current collector facing away from the electrode post. The second single-sided electrode includes a second current collector and a second active material layer. The surface of the second current collector facing away from the electrode post is directly electrically connected to the bottom shell. The second active material layer is disposed on the surface of the second current collector facing the electrode post.

2. The button battery according to claim 1, characterized in that, The button cell includes a first adhesive element that bonds the first current collector to the terminal post.

3. The button battery according to claim 2, characterized in that, The electrode post includes a first wall surface and a first protrusion. The first wall surface is disposed facing the stacked battery cell, and the first protrusion protrudes from the first wall surface. The first protrusion abuts against the surface of the first current collector facing the electrode post. Along the stacking direction of the stacked battery cell, there is a first gap between the first wall surface and the first current collector.

4. The button battery according to claim 3, characterized in that, The first spacing ranges from greater than 0 micrometers to less than or equal to 50 micrometers.

5. The button battery according to claim 3, characterized in that, The first adhesive is disposed between the pole post and the first current collector. The first adhesive has a first clearance channel, and the first protrusion passes through the first clearance channel and abuts against the first current collector.

6. The button battery according to claim 2, characterized in that, The electrode post includes a first wall surface and a first recess. The first wall surface is disposed facing the stacked battery cell. The first recess is disposed on the first wall surface and includes an opening located on the first wall surface. The first adhesive member is disposed in the first recess. The first wall surface abuts against the surface of the first current collector facing the electrode post. The first adhesive member bonds the first current collector to the electrode post.

7. The button battery according to claim 2, characterized in that, The first adhesive is a conductive adhesive and / or a pressure-sensitive adhesive.

8. The button battery according to claim 1, characterized in that, The first current collector includes a first tab and a first body portion connected together. The first tab and the first body portion are integrally formed. The first active material layer is disposed on the first body portion. The surface of the first body portion facing the electrode post is directly electrically connected to the electrode post.

9. The button battery according to claim 8, characterized in that, The button battery includes a first adhesive member that bonds the terminal post and the first body portion.

10. The button battery according to claim 1, characterized in that, The first current collector includes a first tab, a first main body, and a first folded portion connected together. The first tab, the first main body, and the first folded portion are integrally formed. The first active material layer is disposed on the first main body. The first folded portion is folded relative to the first main body. The first folded portion is located between the first main body and the electrode post. The surface of the first folded portion facing the electrode post is directly electrically connected to the electrode post.

11. The button battery according to claim 10, characterized in that, The first folded portion is welded to the terminal post; or, the button battery includes a first adhesive member that bonds the first folded portion to the terminal post.

12. The button battery according to claim 10, characterized in that, The area of ​​the first folded portion is greater than or equal to the area of ​​the first main body portion.

13. The button battery according to claim 8 or 12, characterized in that, The surface area of ​​the electrode facing the stacked cell is greater than or equal to the area of ​​the first main body.

14. The button battery according to any one of claims 1 to 12, characterized in that, The bottom shell has a bottom wall, and the button battery includes a second adhesive member that bonds the second current collector to the bottom wall.

15. The button battery according to claim 14, characterized in that, The bottom wall has a second wall surface, and the bottom shell includes a second protrusion. The second wall surface is disposed facing the stacked battery cell, and the second protrusion protrudes from the second wall surface. The second protrusion abuts against the surface of the second current collector facing the bottom wall. Along the stacking direction of the stacked battery cell, there is a second distance between the second wall surface and the second current collector.

16. The button battery according to claim 15, characterized in that, The second spacing ranges from greater than 0 micrometers to less than or equal to 50 micrometers.

17. The button battery according to claim 15, characterized in that, The second adhesive is disposed between the bottom wall and the second current collector, and the second adhesive has a second clearance channel, the second protrusion passing through the second clearance channel and abutting against the second current collector.

18. The button battery according to claim 14, characterized in that, The bottom wall has a second wall surface and a second recess. The second wall surface is disposed facing the stacked battery cell. The second recess includes an opening located on the second wall surface. The second adhesive is disposed in the second recess. The second wall surface abuts against the surface of the second current collector facing the bottom wall. The second adhesive bonds the second current collector to the electrode post.

19. The button battery according to claim 18, characterized in that, The second adhesive is a conductive adhesive or a pressure-sensitive adhesive.

20. The button battery according to any one of claims 1 to 12, characterized in that, The second current collector includes a second electrode tab and a second main body portion connected together. The second electrode tab and the second main body portion are integrally formed. The second active material layer is disposed on the second main body portion. The surface of the second main body portion facing away from the electrode post is directly electrically connected to the bottom shell.

21. The button battery according to claim 20, characterized in that, The bottom shell has a bottom wall, and the button battery includes a second adhesive member that adheres to the second main body and the bottom wall.

22. The button cell battery according to any one of claims 1 to 12, characterized in that, The second current collector includes a second tab, a second main body, and a second folded portion connected together. The second tab, the second main body, and the second folded portion are integrally formed. The second active material layer is disposed on the second main body. The second folded portion is folded relative to the second main body. The second folded portion is located between the second main body and the bottom shell. The surface of the second folded portion facing away from the pole post is directly electrically connected to the bottom shell.

23. The button battery according to claim 22, characterized in that, The bottom shell has a bottom wall, and the second folded portion is welded to the bottom wall; or, the button battery includes a second adhesive member, which adhesively bonds the second folded portion to the bottom wall.

24. The button battery according to claim 22, characterized in that, The area of ​​the second folded portion is greater than or equal to the area of ​​the second main body portion.

25. The button battery according to any one of claims 1 to 12, characterized in that, The stacked cell includes a first double-sided electrode and a second double-sided electrode. The first single-sided electrode and the second single-sided electrode are alternately stacked. The first single-sided electrode and the first double-sided electrode have the same polarity. The first single-sided electrode and each of the first double-sided electrodes are electrically connected. The second single-sided electrode and the second double-sided electrode have the same polarity. The second single-sided electrode and each of the second double-sided electrodes are electrically connected.

26. The button battery according to claim 25, characterized in that, The first single-sided electrode includes a first tab, and the first double-sided electrode includes a third tab. The first tab and each of the third tabs are gathered together and welded along the stacking direction of the stacked cells to form a first gathered portion, which is a one-piece structure.

27. The button battery according to claim 25, characterized in that, The second single-sided electrode includes a second tab, and the second double-sided electrode includes a fourth tab. The second tab and each of the fourth tabs are gathered together and welded along the stacking direction of the stacked cells to form a second gathered portion, which is a single-section structure.

28. The button battery according to any one of claims 1 to 12, characterized in that, The first single-sided electrode is a cathode electrode, and the second single-sided electrode is an anode electrode.

29. The button battery according to any one of claims 1 to 12, characterized in that, The top cover is directly electrically connected to the bottom shell. The outer shell includes an insulating component that connects the pole post and the top cover. The pole post and the top cover are insulated and isolated by the insulating component.

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